USMLE Step 1 - Question 31

A 7 year old male with a history of a seizure disorder and developmental delay is found to have cortical tubers on brain magnetic resonance imaging. Which of the following cardiac tumors is he likely to develop?

A. Left atrial myxoma

B. Cardiac sarcoma

C. Rhabdomyoma

D. Cardiac lymphoma

This patient has tuberous sclerosis, an autosomal dominant genetic disorder due to mutations in the tumor suppressor gene hamartin or tuberin. Cardiac tumors are most commonly rhabdomyomas in this disorder. Seizures and developmental delay are common. Multiple other tumors may also develop.

Left atrial myxoma (A) is more common in older individuals and can cause a mitral stenosis picture as the tumor obstructs the valve. Cardiac sarcomas (B) and cardiac lymphomas (D) are extremely rare.